Fixed an issue where mousewheel would stop working in some cases after exiting full preview mode.

Fixed a crash when using alt+tab on some configurations.

Fixed a case where parties could incorrectly enter ranked matchmaking.

Fixed portions of the Quit button not accepting clicks.

Fixed a crash launching workshop tools on Windows 7 without Service Pack 1.

Fixed some client crashes.

Rumor has it:

In the event you didn't happen to get the memo: Mac OS X Lion and Mountain Lion are no longer supported as of a few days ago, as after the Source 2 hybridization, you will need Mac OS X Mavericks (10.9), Yosemite (10.10), or soon El Capitan (10.11) to continue to play